The present invention is directed to the containment and detection of fugitive emissions, for example, leaking from valves and bolted flange connections. Also, the present invention is directed to a system for detecting and monitoring emissions. In another embodiment, the present invention relates to enclosures for valves and pipe connections or joints. In another aspect, the present invention relates to novel detectors for the detection of fugitive emissions.
One of the major environmental concerns is the amount of polluting emissions which are leaked directly into the atmosphere due to the failure of present systems. The existing systems are expensive and technically inadequate. It is believed that the two primary sources responsible for over 95% of industrial fugitive emissions are valve stuffing boxes and bolted pipe flange connections used in the oil and gas, and petrochemical industries.
One example of the present state of the art in detection systems includes equipment which monitors large areas; such equipment detects leaks only after the emissions have entered the atmosphere. Another detection system requires an individual to use small, hand-held units in order to detect leaks. This method is unreliable, especially if detection takes place in the presence of even a small cross wind. Both methods allow leakage to continue for significant periods of time before detection and correction can occur. The ever stricter standards set by environmental agencies has led to the need for a more effective and efficient monitoring system for fugitive emissions. The present invention provides a solution to eliminate 95% of the fugitive emissions.
The present invention is directed to a monitoring system which detects fugitive emissions, for example, those leaking from valves and bolted flange connections in the oil and gas, and petrochemical industries. The invention is also directed to systems applicable in the chemical, pharmaceutical and the food processing industries. The system of the present invention may be comprised of a set of enclosures, a set of detectors for the enclosures, a set of signalers in communication with the detectors, and, if desired, a central processing location for monitoring the status of the enclosed sites.
The present invention is also directed to novel enclosures for pipe flange connections and valve stuffing boxes as used in the oil and gas, and petrochemical industries. The pipe flange connection enclosures are comprised of members, preferably two semi-circle shaped members, which when combined encompass the flange connection. The members form a centrally located internal channel. On either side of the centrally located channel are walls, preferably of gaskets or seals, such that when the semi-circle members are joined around or encompass a pipe flange connection, the centrally located channel forms an enclosure around the gasket area between the pipe flanges of the connection. The channel of one of the members includes a port for sealably receiving a detector of the present invention. Alternatively, one of the members also includes a port in the channel for receiving a vent plug.
The present invention is also directed to new enclosures for valve stuffing boxes. The valve stuffing box enclosures are preferably comprised of two members or half-pieces preferably shaped when joined like a hollow frustrum, i.e., it is frustro-conical in shape when joined. Each member may include, according to one embodiment, gaskets or seals around the inside top portion, i.e., the narrow end of the frustrum and at the inside bottom portion, i.e., the wider end of the frustrum. In addition, one member of the pair includes lengthwise channels for receiving the other member having lengthwise gaskets or seals.
In a preferred embodiment, the valve stuffing box enclosures of the present invention are comprised of two members or half-pieces (mirrored pieces/halves) that when joined are preferably shaped like a hollow frustrum. Preferably, the enclosures do not include any gaskets or seal-type material around any of the edges of the members. Preferably, each member includes a receiver to receive a side of the other half to form a mechanical connection between the two halves. The receiver of one half and the opposing side of the other half when joined form a mechanical seal such that emissions leaked from the valve stuffing box are reliably detected by the detector in communication with the inside space of the enclosure.
The invention is also directed to valve stuffing box enclosures comprising first and second members (mirror image half-pieces) having an inside and an outside, the outside having preferably, a greater circumference than the inside. Each member includes a receiver on the inside running vertically along an edge of the member, preferably for a majority of the length of said member. The receivers are constructed preferably as folds or pleats integral with the member such that they accept the other member when joined together to form a mechanical seal on the inside of the members sufficient to ensure reliable detection by a detector associated with the enclosure.
The valve stuffing box enclosures are preferably used in conjunction with the pipe flange connection enclosure. The valve stuffing box enclosures are designed to overlap and connect to the pipe flange enclosure forming a heretofore unknown and unrealized combination for the containment and detection of emissions from valve stuffing boxes.
The present invention is also directed to a heretofore unknown adsorption detector. The preferred detector is comprised of a substrate, e.g., metal or ceramic, electrode elements, adsorbent particles, like carbon, of substantially the same size, and an elastomer or a binder type gas permeable material. Preferably, the detector is operated in a non-current saturated mode or in a linear region and can detect substances having a Van der Waals xe2x80x9caxe2x80x9d constant of less than about 9. Optionally, if desired, the detector may include non-adsorbent particles. Further, if desired, the detector may include a temperature detector or sensor. In some systems, for example, smaller systems, an indicating cartridge can be used as the detector and signaler. For instance, chemical-treated granules affixed to paper or chemical granules will change color when a threshold emission occurs. The indicator material (or detector/signaler) is enclosed in a housing, like a cylinder, which is installed or connected to the enclosures of the present invention. It is the main object of the present invention to provide a monitoring system to detect emissions before any significant amounts reach the atmosphere which is both convenient and inexpensive to use.
It is another object of the present invention to provide a monitoring system for valve stuffing boxes and pipe flange connections as used in the oil and gas and petrochemical industries.
It is another object of this invention to provide novel enclosures for pipe flange connections and valve stuffing boxes.
It is another object of the present invention to provide novel adsorption detectors for detecting fugitive emissions at heretofore unmeasurable low levels in the field.